How to bypass the Neutral Safety Switch
01-10-2010, 05:24 PM
#16
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Year: 1987
Model: Cherokee
Engine: 4.0
you need to splice wires B and C on the NSS connector together in order to bypass the neutral safety.
this will NOT affect the rest of the NSS...it will still tell what location the NSS is in (R, OD, 3, 1,2) unless it's completely junk inside.
remember, when you're doing splices like this, to do it on something that's replaceable....I.E. DO NOT splice the engine harness B and C wires together....splice the wires that are on the NSS harness on the NSS side of the connector.
this will NOT affect the rest of the NSS...it will still tell what location the NSS is in (R, OD, 3, 1,2) unless it's completely junk inside.
remember, when you're doing splices like this, to do it on something that's replaceable....I.E. DO NOT splice the engine harness B and C wires together....splice the wires that are on the NSS harness on the NSS side of the connector.
01-10-2010, 10:31 PM
#18
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Year: 1987
Model: Cherokee
Engine: 4.0
the NSS has several different functions. the N and P "selections" run through the B and C wires on the connector.
the rest of the functions (I.E. reading R as well as 1,2 3 and OD) are reserved for other wires end result, cutting out the actual "start" circuit from the NSS will not affect the transmissions shifting ability.
the rest of the functions (I.E. reading R as well as 1,2 3 and OD) are reserved for other wires end result, cutting out the actual "start" circuit from the NSS will not affect the transmissions shifting ability.
01-12-2010, 09:52 AM
#19
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Year: 1996 Country
Model: Cherokee
Engine: 4.0L HO I6
so now the tip of the hollow bolt holding the retaining nut broke off with hardly any force at all (looked severly oxidised)...there are still enough threads left to put it on, but i dont wanna try to pry with it on anymore as if 8 threads didnt hold it, im sure 3 wont...anybody have any other suggestions? it slides out like butter the first half inch then stops, ive messed with it for 3 days now and it wont budge...and other tips? i wasnt trying to but now i might just jump the start circuit (leave the others so itll still control the tranny)...
10-16-2010, 08:25 PM
#21
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FYI, it is correct that shorting the 2 black wires comign from the switch will make it start in any gear. i did this and it worked but I have cruise and it broke the cruise until I "udid it". Anyone know another way?
10-16-2010, 08:41 PM
#22
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Year: 1994 1993
Model: Cherokee
Engine: 4.0
This is interesting. Since all the black wires do is complete the ground for the starter motor I'm curious how connecting just these two could affect anything else.
10-16-2010, 08:53 PM
#23
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It was conclusive. I had shorted the 2 black wires and it fixed the start issue but broke the cruise. I undid it and broke the start issue and fixed the cruise. I wish I knew more about the wire functions coming up from that switch. Wonder if there is an actual speed impulse coming up one of those black wires to the ECU?
10-16-2010, 09:23 PM
#25
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Looking at post #6 here in this thread https://www.cherokeeforum.com/f2/wir...s-93-xj-32698/ it says that wires for pins B & C need shorted. I just looked at the wiring diagram and pin C going to the TCU is labeled "Road Speed". Also, the figure for the switch showing wire "C" comes from "Reed SW" which is right beside a figure of a rotating shaft labeled Magnetic Trigger. That is where I gather that wire has some sort of pulse that the cruise uses.
10-16-2010, 09:31 PM
#27
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Stand down. I was wrong. i bet the NSS is the switch above the TCU called "Gear selector switch". I will revisit this topic again and see what the heck could be related to my cruise coming back to life when I reverse the shorting of the black wires.
Last edited by PCweber; 10-16-2010 at 09:50 PM.
10-17-2010, 01:09 AM
#28
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Year: 1993
Model: Cherokee(XJ)
Engine: 4.0 i six H.O.
maybe that is whats wrong with mine, i was told there isnt any power going to my tcu and it does shift kinda funny at times. sometimes when i slow down for a red light and it changes and im still like in, i believe 2nd gear, i hit the gas and then i get stuck in 3rd until i compleatly stop. ill be doing 55 and the tach is showing around 2500 rpm's or so.
10-17-2010, 08:11 AM
#30
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Year: 1994 1993
Model: Cherokee
Engine: 4.0
These are just ground wires. They don't carry any signals or power. I don't even know if "shorted" is the correct term for a ground wire.